1. Field of the Invention
The present invention relate to a refrigerating apparatus for use in transportation, and more particularly to such refrigerating apparatus in which a compressor is driven by an engine, and a condenser fan for feeding external air to a condenser and an evaporator fan for feeding air in a freezing chamber to an evaporator are driven by the same engine.
2. Description of the Prior Art
One example of a refrigerating apparatus for use in transportation in the prior art is illustrated in FIGS. 4 and 5. This apparatus has a so-called nose mount shape, which means that it is mounted to the outside of a front wall 13a of a freezer compartment 13 of a vehicle. The interior of a main body 20 of this refrigerating apparatus is partitioned into a machine housing 21, and an outdoor side airflow passageway 22 and an indoor side airflow passageway 25. In the machine housing 21 are disposed an engine 1, a compressor (not shown) which is driven by this engine 1, and an electric motor 2 for driving the compressor with a commercial power source. In the outdoor side airflow passageway 22 are disposed a condenser 7 and a propeller type of condenser fan 8 for feeding external air to this condenser 7. An intake opening 23 through which external air is led to the condenser 7 and an exhaust opening (not shown) through which air flowing past the condenser 7 is discharged are defined on a side of the main body 20. In the indoor side airflow passageway 25 are disposed an evaporator 11, and a turbo type of evaporator fan 12 for feeding air in the freezer compartment to the evaporator 11. Also, a guide plate 26 leads air in the freezer compartment to the evaporator 11, and a blow-out opening 28 allows air having passed the evaporator 11 to blow into the freezer compartment.
As shown in FIG. 5, the condenser fan 8 and the evaporator fan 12 are connected via a common drive shaft arranged in the direction perpendicular to the drive shaft of the engine 1, and they are driven by a belt via an electric motor 2 for transmitting power from the engine 1. The direction of the belt is changed and adjusted by means of a large number of pulleys disposed at various locations in the main body of the apparatus. In the outdoor side airflow passageway 22, external air sucked through the intake opening 23 by the condenser fan 8 absorbs heat from the refrigerant flowing through the condenser 7, and thus condenses and liquefies the refrigerant, and thereafter is discharged through the exhaust opening.
On the other hand, in the indoor side airflow passageway 25, air in the freezer compartment forced along the guide plate 26 by the evaporator fan 12 is cooled by delivering heat to a refrigerant flowing through the evaporator 11, and is blown out as a cold airflow through the blow-out opening 28 into the freezer compartment.
In the above-described refrigerating apparatus for use in transportation in the prior art, because of the fact that different types of fans are used for insuring a sufficient airflow to the condenser 7 and the evaporator 11, that is, because the condenser fan 8 consists of a large propeller type of fan and the evaporator fan 12 consists of a turbo type of fan, the manufacturing cost of the apparatus is high.
In addition, because the drive shafts of the condenser fan 8 and the evaporator fan 12 are disposed perpendicularly to the drive shaft of the engine 1, transmitting power from the engine 1 involves changing the direction of the rotary output of the motor and so the transmission must have a complicated structure.